Thermal transport properties of functionalized graphene/palmitic acid phase‐change composites: A molecular dynamics study

• Published in: Polymer composites 2023-07, Vol.44 (7), p.4109-4120
• Main Authors: Che, Deyong, Zhang, Shengxu, Gao, Long, Sun, Baizhong, Tong, Xiaohui, Gegentana
• Format: Article
• Language: English
• Subjects: composite; Composite materials; Energy storage; Fatty acids; Functional groups; functionalized graphene; Graphene; interfacial thermal resistance; Molecular dynamics; molecular dynamics simulation; Palmitic acid; Phase change materials; Phase transitions; phase‐change material; Storage systems; Thermal energy; Thermal resistance; Thermodynamic properties; Transition temperature; Transport properties
• ISSN: 0272-8397; 1548-0569
• DOI: 10.1002/pc.27383

Considering the importance of high‐performance composite phase change materials (PCMs) for the realization of efficient thermal energy storage, molecular dynamics simulations were conducted in this study to investigate the thermal properties of graphene/palmitic acid composites and the related interfacial thermal transport. The effects of the interactions between functionalized graphene and fatty acids on the thermal transport properties needs to be investigated further. The addition of functionalized graphene (with epoxy, hydroxyl, and carboxyl groups) increased the phase transition temperature and decreased the specific heat capacity of the PCM, whereas both of these parameters increased with increasing functional group coverage (FGC). Further the effects of the FGC and functional group type on the interfacial thermal resistance (ITR) were investigated by analyzing the interaction energy and vibrational density of states, and the ITR decreased with increasing FGC. Compared to that of pure PA, the phase‐transition temperatures of the PA/pristine graphene composites were higher by ~7 K. The ability of functional groups to decrease the ITR decreased in the order of epoxy